Joannes or John Zonaras (c. 1070 – c. 1140) was a Byzantine historian, chronicler and theologian who lived in Constantinople. Under Emperor Alexios I Komnenos he held the offices of head justice and private secretary (protasēkrētis) to the emperor, but after Alexios' death, he retired to the monastery on the Island of Hagia Glykeria, (İncir Adası, in the Bay of Tuzla), where he spent the rest of his life writing books.